The use of magnetic adhesives has been disclosed in the art. For example, Kassab and Navia disclosed a surgical use of a magnetic endograft in a lumen, positioned inside the aorta, to attract a magnetic glue-like substance injected outside the aortic wall for endovascular aneurysm repair. See WO 2008/091561 to Kassab and Navia, incorporated herein by reference. However, no method for cleaning unwanted adhesive near a surgical site in a patient's body was taught or suggested by Kassab and Navia. Most other disclosures related to magnetic adhesives have concerned magnetic excitation of ferromagnetic particles embedded in an adhesive to heat and thereby accelerate curing of the adhesive, and/or the enhancement of the magnetic flux carrying capacity of the adhesive after it is cured. Ferrofluidic lubricants have also been disclosed, as have seals to contain such ferrofluidic lubricants.
However, there are many situations of commercial and/or medical importance where the extent of an adhesive must be carefully controlled to prevent undesired spread, and/or where undesired spread of adhesive must be carefully and thoroughly cleaned.
For example, adhesive has been used in certain orthopedic surgical procedures, such as an orthopedic surgical procedure to replace a natural but pathologic patello-femoral joint with an artificial patello-femoral joint or prosthesis. Various such methods have been used or proposed, such as that described in U.S. Patent Application Publication 2003/0181984 to Abendschein (teaching a patello-femoral joint replacement method in which an adhesive is used to bond the underside of a femoral implant to a prepared anterior surface of the femur, and incorporated herein by reference). Also for example, the use of adhesive has been employed in orthopedic surgical procedures to replace a natural but pathologic hip joint with an artificial hip joint or prosthesis (see, e.g. Japanese Patent JP 2528572 to Lawes).
In such surgical procedures, it is desirable that any adhesive that is used remain in a desired region (e.g. near the interface between the patient's bone and a surface of the prosthesis or a joining fastener), and not spread into other tissues or regions of the patient's body. However, in certain contemporary orthopedic surgical procedures, the physician must perform additional steps to contain the extent of the adhesive used, and in some cases the surgery may become more invasive to clean adhesive that has undesirably spread to other tissues. Hence, there is a need in the art for an improved method to control and limit the spread of adhesive during surgical procedures. There is also a need in the art for an improved method to clean or remove unwanted adhesive from a patient's tissues during or after a surgical procedure in which an adhesive is used.
Also for example, controlling the spread of adhesive for assembling or joining components in a reduced gravity environment (e.g. outer space) can be important, because the spread of unwanted adhesive droplets may contaminate optical lenses and/or interfere with or cause failures in related or unrelated systems. Hence, there is a need in the art for methods to clean or limit the extent of adhesives in outer space assembly and repair operations.
Also, for example, in the manufacture of hard disk drives, the magnetic recording head is adhered to the tongue of a thin laminated flexure by an adhesive (e.g. a UV-curable or electrically conductive epoxy). However it is important that the adhesive does not spread beyond a desired area on the flexure tongue, or else the adhesive might contaminate the disk drive or interfere with subsequent disk drive fabrication steps (e.g. the electrical connection of the head to conductive traces on the thin laminated flexure). Hence, geometrical features have been disclosed, which have been etched or deposited on the thin laminated flexure to control the spread of the adhesive. Such geometrical features, however, may not benefit or be compatible with other requirements for the laminated flexure structure. Accordingly, there is a need in the art for an improved method for controlling the spread of adhesive in commercial manufacturing processes. There is also a need in the art for an improved method to clean or remove unwanted adhesive from fabricated components and/or manufacturing apparatuses during or after commercial manufacturing processes.